from django.db import models
from pygments.lexers import get_all_lexers
from pygments.styles import get_all_styles
from pygments.lexers import  get_lexer_by_name
from pygments.formatters.html import HtmlFormatter
from pygments import highlight

LEXERS = [item for item in get_all_lexers() if item[1]]
LANGUAGE_CHOICES = sorted([(item[1][0], item[0]) for item in LEXERS])
STYLE_CHOICES = sorted((item, item) for item in get_all_styles())


class Snippet(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    title = models.CharField(max_length=100,
                             blank=True,
                             default="")
    code = models.TextField()
    linenos = models.BooleanField(default=False)
    language = models.CharField(choices=LANGUAGE_CHOICES,
                                default="python",
                                max_length=100)
    style = models.CharField(choices=STYLE_CHOICES,
                             default="friendly",
                             max_length=100)
    owner = models.ForeignKey("auth.User",
                              related_name="snippets",
                              on_delete=models.CASCADE)
    highlighted = models.TextField()

    class Meta:
        ordering = ('created',)

    def save(self, *args, **kwargs):
        lexer = get_lexer_by_name(self.language)
        linenos = self.linenos and "table" or False
        options = self.title and {"title": self.title} or {}
        formatter = HtmlFormatter(style=self.style,
                                  linenos=linenos,
                                  full=True,
                                  **options)
        self.highlighted = highlight(self.code, lexer, formatter)
        super(Snippet, self).save(*args, **kwargs)
